Comparação de métodos de extração de fumonisinas e ocratoxina A em milho

Abstract

Maize is one of the main cereals produced in the world and has great relevance in human food and animal protein production. It is a grain highly susceptible to contamination by mycotoxins, mainly fumonisins and ochratoxin A, which are toxic products resulting from the secondary metabolism of filamentous fungi such as Fusarium, Aspergillus and Penicillium, respectively. The objective of this work is to compare the creation of a new extraction solution with a certified and validated methodology for the recovery of fumonisins and ochratoxin A. To achieve this objective, experiments were carried out with 20 samples of ground corn and free of contamination by fumonisins and ochratoxin A. After homogenization, the samples were separated into two groups for preliminary tests using the extraction solution with MeOH:H2O (80:20, v:v) in group A and the extraction solution with ACN:H2O:AF (80:19.9:0.1, v:v:v) in group B. From the results obtained from these preliminary tests, the solution A was chosen for the validation test and modified with the addition of 5g of NaCl and only fumonisins were considered for the comparison of methods. This procedure lasted for three consecutive days and after reading and analyzing the HPLCMS/ MS, the average recovery results obtained on the 1st, 2nd and 3rd days were 41.2%, 48.9% and 22, 3% and 58.6%, 45.9% and 53.9% for FB1 and FB2, respectively. The comparison of these results with the methodology used in the laboratory, shows differences in the organic solvent used and also in the recovery, which was found between 97-99% being within the range of acceptance by the Commission Regulation. With the results obtained, it was possible to conclude that the extraction solution created did not interact correctly with the target mycotoxins, resulting in recoveries below 60% showing a great difference compared to the excellent recovery of the official and certified laboratory methodology.